This invention relates to automatic door closing devices, and, in particular, to offset pivot hinges with automatic door closing mechanism.
A well known pivot door hinge comprises a plate having a pivot pin secured thereon and another plate pivotally mounted on the pivot pin. One of these plates is mounted on the floor or the door frame. Thus, the door is rotatable around the vertical pivot axis for opening and closing.
One type of such a pivot hinge is known as an offset pivot hinge wherein the pivot pin axis is offset from the vertical door edge.
It has also been desired to have an automatic door closing mechanism for such door hinges. In the existing pivot hinges having door closing mechanism, the mechanism is assembled onto one of the hinge mounting plates or within a housing secured onto the plate.
When installing a door using hinges having a door closing mechanism, the installation operation is difficult because of the existence of door closing torque in the mechanism. The large volume of the hinge also makes the installation operation difficult.
When an automatic door closing function is required for doors using conventional pivot hinges, exchange of the used hinge for a hinge having the door closing mechanism must be easily accomplished.